This is talking from the direction of actively engaging a large business and selling to them. I work on the side of large business actively choosing which startups we want to work with.
"Lesson 1: In larger organizations there are multiple individuals with separate motivations involved in the buying process "
Without question this is important. I am sort of a gatekeeper in the process. It's my job to validate the companies that are seen by the real decision makers (not me). I am the technical grunt in front of the process allowing the C level decision makers to only make good decisions no matter what they decide to do.
With me, you can discuss tech on a geek level, and I'm most comfortable and at home.
To my C levels, you better be high level and respectful. We've lost the ability to work with several startups simply because they weren't able to discuss on a C level.
If you are a founder and can't discuss on a C level, hire someone who can. You could lose a tremendous level of money and momentum simply because you have no idea how to talk to someone who leads a large business.